Stand-up filters of the type discussed here serve for making filtered drinks, especially coffee drinks, in a simple way. The stand-up filter is intended to be used only once and is adapted to be stood on the edge of a vessel, especially on the edge of a cup. A portion of a substance for making the drink, especially ground roasted coffee, is introduced into the upwardly open filter bag. The drink is made directly by means of (brewing) water poured into the filter bag from above, and the stand-up filter is then discarded as a whole. In the making of coffee drinks, the portion of ground roasted coffee may also be already present in the filter bag as a result of appropriate production.
Simple handling and cost-efficient production are factors to be taken into account in the constructive design of stand-up filters of this type. It is necessary, furthermore, that the stand-up filter which is unfoldable into a three-dimensional shape for the preparation of the drink, can be folded into a flat configuration for packaging. In this storable initial form in which the filter is ready for dispatch, foldable stand-up filters of this type are conventionally packaged in an outer wrapping, especially a foil bag.
The supporting members conventionally consist of thin cardboard (paperboard). It is important to design the supporting members so that they are as small as possible and can likewise be folded together in a flat configuration for packaging, but nevertheless, when unfolded, guarantee that the stand-up filter has sufficient firmness and stability.